In the analysis of biological samples such as cells and biological materials such as proteins and nucleic acids, an operation for previously separating and purifying the sample and an operation for separating the sample according to sizes or electric charge are performed prior to the analysis. For example, in proteomics analysis, usually mass spectrometric analysis is used for the analysis of a separated component. When the component contained in the sample provided for the mass spectrometric analysis is a biological component such as a protein, a nucleic acid, and a polysaccharide, conventionally it is necessary that the target component is previously isolated from the biological sample. For example, when the analysis of the sample containing the plural components is performed, the sample has been purified, the separation has been performed in each component by a two-dimensional electrophoresis, each component has been recovered from each separated spot, and the sample for mass spectrometric analysis has been prepared with the recovered component. Therefore, it is necessary that the separation process and the sample preparation process are separately performed, which complicates the operation.
There is studied a method in which the component separation in the sample and the mass spectrometric analysis are efficiently performed for the purpose of eliminating such the complicated operation (Patent Documents 1 and 2). Patent Documents 1 and 2 describe a mass spectrometry apparatus, in which a capillary tube for performing the electrophoresis and an ionizing unit for performing the mass spectrometric analysis are integrated to continuously perform the electrophoresis and the mass spectrometric analysis. However, in this kind of apparatus, it is necessary that the mass spectrometric analysis is performed point by point for the component recovered from the capillary tube. Therefore, there is still room for improvement from the viewpoint of analytical efficiency. Further, because a configuration of the apparatus becomes a large scale, there is also still room for improvement from the viewpoint of space saving.
Recently research and development of a microchip in which a function of separating or analyzing substances derived from a living organism is included on a chip is actively performed. Patent Document 3 describes the mass spectrometry in which the microchip is used. In the method described in Patent Document 3, a probe to which an adsorbent is coupled is provided in a bottom surface of a substrate, a specific component in the sample is adsorbed by the adsorbent to separate the components by bringing the substrate into contact with the sample, and then the mass spectrometric analysis is performed in each probe.
However, in the method described in Patent Document 3, it is necessary that the absorbent corresponding to each component in the sample is selected to prepare a probe substrate in which the selected adsorbent is immobilized. Then, the sample is spotted on the probe, and it is necessary to wash and remove the unnecessary component. Then, the adsorbed component is sequentially ionized in each probe to perform the mass spectrometric analysis. Therefore, the separation and the analysis of the sample are not continuous, and the operation is relatively complicated.
Patent Document 1: Japanese Patent Application Laid-Open No. H5-164741
Patent Document 2: Specification of Japanese Patent No. 2572397
Patent Document 3: Japanese Patent Application Laid-Open No. 2001-281222